mx5cartalk.com

Please advise correct minimum offset required for 15"x 8 wheel for an SE.
Also would a 225 tyre be too wide without rolling guards ?
Thanks

What do you mean by correct?
Legal?
Aesthetically?

Sent from my LG-H815 using Tapatalk

Minimum offset required to clear the brakes ................
I believe the OEM Racing Harts are +40 ?

There's no minimum offset to clear the brakes, as every wheel is slightly different. For example one wheel may clear at +40, whilst another may foul.
Are you looking at a particular wheel design?

No problems running 15x8 6ULs (offset +36) with 225/45/15s on mine (225/50/15s will rub your guard liners).

I believe that NAs require guard rolling, NBs are fine.

Thanks Lokiel, noted.

Looking at Rota Grid 15x7 +38 or Rota Slipstream 15 x7 +35
If I go with 15x7 I'll use 205/215 x 50 tyres

As above, offset is more to do with clearing suspension and body panels than brake calipers.

Caliper clearance is mostly affected by the clearance between mounting face and inner spokes. Which depends on how the wheel is constructed.


Offset wise, a 15x8 +25 is about as low of an offset as you can go before you need to consider other work to prevent the tyres clipping the guards (a 205 on that wheel just clears the guard, a wider tyre will hit)

With a 225 tyre you'd most likely need to increase the offset by 10mm give or take to miss the guard, so you'd want around the +35 mark.

just to add if anyone goes looking for this in the future if you want 15" Enkei rpf1s to fit over nb8b brakes, you will need the 15x8+28. when i was looking at RPF's i thought i would go this way if i did the brake upgrade in the future. i ended up getting bead blasted ssw peaks like a bronze RPF1 15x7 30 offset, slightly heavier at 5.2kg on kitchen scales (VS 4.4kg of RPF) but half the price and people on here have tracked them, im not sure if these would clear but i wont be running the NB8B brakes now anyway.
Also i know in the past that there was quite a few reports of ROTA's cracking which put me off them as they make some nice looking wheels but it seems less reported now so either they have fixed up issues or less people are buying them but maybe do some research, also some models are a little heavy and i would advise finding something lighter or the same weight as what you have but i imagine most should be lighter or the same as the standard SE Harts.

from mazda-speed.com

"Here's a good site with weights for most, if not all North American Miata wheels: http://www.jason-parker.net/images/wheels.htm -- they claim the '04 Racing Harts are 17.1 lbs and the '05s are a piggy 18.4!"

as i said my SSW's are 5.2 so around 11.5 pound for comparrison.

Thank you all for the great input.
Will probably go with Rota Classic 15x7 +10 as I know they fit an SE.
Then run 205 or 215 x 50 tyre.

I am running Buddy Club P1's 15x8 with +32 offset on my SE. You can fit your hand between the spokes and the callipers with these.
Had both Hankook RS3 225/45/15 and Nitto NT01 with 225/45/15 with no rubbing.
I have not rolled my guards or removed any liners.
Most importantly this is with Tein Street Flex Coilovers fitted and front upper arm Delrin offset bushes for more negative camber. I have heaps of room on the fronts on the outside.
-3°15' camber at the front and -2°40' camber at the rear

I also had 16x7 +40 with 225/45/16 Kuhmo V70A and they just touched the top of my 2 front guard liners and wore a small 10mm hole in each.
They also just touched near the spring perch on the body, which only occurred because of the offset bushes I have fitted.
This setup has the same rolling diameter as 225/50/15.

jezman wrote:Thank you all for the great input.
Will probably go with Rota Classic 15x7 +10 as I know they fit an SE.
Then run 205 or 215 x 50 tyre.

You'll need to roll the guards and possibly pull them a bit as well to fit a +10 offset rim on your SE, especially if running a 215/50 tyre. I had to roll guards to fit 215/50 on +25 rims on my NB, and they make a mess of the inner guards with rubbing still.

205/50/15 A050 on 15x8 +22s needed a slight fender roll and cut wheel liner when my car was lowered with full factory camber.


225/50/15 A050 on 15x8 +22s needed offset bushes, the guards rolled a bit more and the car raised a bit


225/50/15s A050 on 15x8 +20 needs a bit more of the rear guard rolled I think.

Great advise keeps on coming thank you.

Decided to buy 6UL's 15 x 8 +36 from Mania.

Prefer Advan 050's but they don't do 45 x 15 .............
So thinking about 215 50 15 which are available soon .......
Then roll the guards if needed.

Will also fit MCA X-R coil overs.

I'm on my 2nd set of AO50 215/50/15s, they've been out for at least 18 months.

Thanks Okibi
Been quoted 2 weeks delivery on 215 50 15. No problem, can wait ok.
Love your SE looks very purposeful

And thanks Luke for your very detailed info.